Genus LOPHOPHYLLIDIUM Grabau, 1928
Characteristics of Lophophyllidium, as determined from study of the genotype species and other Upper Carboniferous and Permian material, are summarized in the following description.
The genus includes medium-sized, straight to curved, solitary corals of conical to conical-cylindrical shape. The theca bears well developed longitudinal grooves and ridges that are crossed by transverse growth lines and wrinkles of varying prominence. The depth of calyx is moderate in some forms, large in others. A prominent solid axial column projects upward in the center of the calyx. The septa are straight and thin in adult forms but may be curved and rhopaloid (thickened at their inner margin) in youth. The counter septum is extended so as to join the axial column, and the cardinal septum is shortened. Other major septa reach almost to the center but are not joined directly to the column. Minor septa may be well developed or absent. Counter quadrants are much accelerated. A conspicuous open fossula is formed by the partial abortion of the cardinal septum and alar pseudofossulae are developed in immature stages. Tabulae arch upward in varying degree and either extend from the periphery to the axial column or become slightly anastomosing. Dissepiments are absent. The characteristic axial column, a solid rodlike structure that in most specimens is compressed laterally, is formed by the thickened axial part of the counter septum and the very steeply upbent axial portions of the tabulae, thickened by steroplasm. Near the calyx the column may be separate from the counter septum. The median lamella of the column is a direct continuation of that in the counter septum. A few short lateral lamellae may be present.
Cyathaxonia prolifera McChesney, Missouri series, Pennsylvanian (Upper Carboniferous), Springfield, 111.; also reported, probably incorrectly, from numerous other Upper Carboniferous and Permian beds of North America, Europe, and Asia.
The genotype of Lophophyllidium was designated as Lophophyllum proliferum (McChesney) by Grabau (1928, p. 99) in the original description of the genus, but some differences in interpretation of the type have developed. Heritsch (1936a, p. 109) selected as "lectotype" the specimen described by Yakovlev (1903, p. 1) as Lophophyllum proliferum (McChesney). This form is also given by Chi (1938, p. 161) as the "genolectotype" of Lophophyllidium. A lectotype is a specimen, selected from a number of specimens upon which an author based a species (Arkell 1933, p. 601; Schenk and McMasters, 1936, p. 6). Inasmuch as the material studied by Yakovlev was not part of that used by McChesney in describing the species, the Russian specimen cannot become a lectotype. Yakovlev's specimen cannot be a neotype of L. proliferum because it does not come from the type locality of the species. Smith (1934, p. 129) has published the opinion that the form described by Yakovlev is not conspecific with L. proliferum (McChesney) and that it belongs instead to Lophophyllum orientals Smith. Fomitehev (1938, p. 220) has redescribed Yakovlev's specimen, designating it a new species, Lophophyllidium yakovlevi.
A number of new species, such as Lophophyllidium newelli, L. minutum, L. distinctum, L. sp. A, and L. sp, B, differ from others referred to this genus in the restriction of the immature characters to a very small part of the apical region, the scarcity or absence of tabulae, and the large alar pseudofossulae. The youthful septa are separated into four symmetrical groups by the cardinal fossula, the two prominent alar pseudofossulae, and the two large interseptal spaces between the counter laterals and the counter septum. Mature parts have very straight septa with little or no axial thickening. Minor septa are very short or absent.
The lack of tabulae indicates similarity to Malonophyllum. The inadequate nature of the illustrations, lack of description of sectioned material, poorly preserved silicified type material, and the manner in which some structural features are described give reason for question as to the actual nature of the genotype described by Okulitch and Albritton (1937, p. 24) as Malonophyllum texanum. The lack of tabulae alone does not seem to be a satisfactory basis for the generic sub-division of lophophyllid corals. Both the incompletely known genotype and the Permian species called M. kansasense Moore and Jeffords (1941, p. 76) show lack of distinct alar pseudofossulae, more prominent rhopaloid septa, and a more independent axial column in the upper part of the corallite. Inasmuch as the significance of the distinctive features observed in this group of new corals is not known, corals of the L. newelli type are not now separated from Lophophyllidium.
Lophophyllidium proliferum (McChesney)
Plate 1, figures 1-3; plate 8, figure 2
[Note: Synonyms include only those forms sufficiently well illustrated and described to permit determination of significant features.]
Cyathaxonia prolifera McChesney, 1860, Descr. new Paleozoic fossils, p. 75; 1865, Illustrations of new species of fossils, pl. 2, figs. 1-3; 1867, Chicago Acad. Sci. Trans., vol. 1, p. 1, pl. 2, figs. 1-3.
Lophophyllum proliferum Meek and Worthen, 1873, Illinois Geol. Survey, vol. 5, p. 56, pl. 24, fig. 1.
[not] Cyathaxonia prolifera Foerste, 1887, Denison Univ. Sci. Lab., Bull., vol. 2, p. 86, pl. 8, fig. 15.
[not] Lophophyllum proliferum Kayser, 1883, in Richtofen, China, Bd. 4, Abh. 8, p. 194, pl. 29, figs. 7-10—Soschkina, 1925, Soc. Nat. Moscow, Bull., sec. geol., n. s., vol. 33, p. 88, pl. 2, figs. 7, 7a; 1928, Same, vol. 5, p. 371, pl. 12, figs. 15-18, text fig. 14.—Schindewolf, 1930, Palaeont. Zeitschr., Bd. 12, p. 220, text fig. 15.—Heritsch, 1931, Abh. Geol. Bundesanstalt, Bd. 23, Heft 3, p. 5, text fig. 1.—Huang, 1932, Palaeontologia Sinica, ser. B, vol. 8, fasc. 2, p. 23, pl. 2, figs. la-d.
This species was originally described on external features alone, the internal features being indicated only by weathered calices. The description of this species by McChesney (1860, p. 75) is quoted in full.
Coral pointed below, gradually widening to the top in the form of a reversed cone, bent in a horn-like curve, sometimes nearly straight; circular, cavity moderately profound; radiating lamellae often more or less distorted, numbering at the margin from thirty-five to fifty according to the size of the individual; often every alternate one only extending a short distance from the margin.
Columella or axis comparatively large lenticular in outline in its free portion, the greater diameter being in the direction of the curvature, and sometimes becoming almost or entirely cylindrical below.
Surface marked by distinct, narrow, rounded longitudinal ribs, crossed by bands or wrinkles of growth of irregular width, which in an occasional specimen present a few short spines or tubes.
The usual height is from one-half an inch to an inch; diameter of the calyx very variable.
Geological position and locality--In the Coal measures, very widely distributed in the Western States.
The revised publication (1867, p. 1) is identical with this except for the statement of geological position and locality. This is given as "in the coal measures at Springfield, Ill., and widely distributed throughout western U.S.A."
There is no record of the specimens used by McChesney in his original description and they are presumably lost. J. Marvin Weller of the Illinois Geological Survey, has kindly loaned to me 9 specimens of a lophophyllid coral from the "Coal Measures near Springfield, Illinois," collected by A. H. Worthen, stating that "most of the fossils recorded from the 'Coal Measures of [Springfield] Sangamon county, Illinois,' in Worthen's time were obtained from the Trivoli cyclothem." He also indicates that there is no known place in the county where equally well preserved corals can be obtained from the beds above coal No. 8.
In external details the lophophyllids from the Worthen collection show much similarity to the illustrations given by McChesney. Indeed, each of the three figures accompanying the original description can be duplicated almost perfectly by one of the specimens sent by Dr. Weller. The specimens also fit the description in nearly every detail. There is no indication of radicles on any of the specimens however. McChesney gives the number of septa in this species as 35 to 50, but he included the minor as well as the major septa in this count. There are about half this number of major septa in corallites of the Worthen group of specimens. The illustrations of other specimens from the same horizon given by Meek and Worthen (1873, pl. 24, figs. 1a-d), seemingly somewhat generalized, are essentially identical.
Inasmuch as McChesney's types are lost and the corals sent to me by Dr. Weller come from as close to the type locality as can be determined from the original description, and inasmuch as they conform almost exactly with the description and illustrations of the original specimens, it seems desirable to designate one of them as a neotype of the species Cyathaxonia prolifera McChesney, the genotype of Lophophyllidium. The description of L. proliferum based on this neotype is as follows:
Solitary conical corallites with the lower one-third curved through an arc of nearly 90 degrees in the plane of the counter-cardinal septa are included in this species. The theca is moderately thick, having deep relatively narrow septal grooves and broadly rounded symmetrical interseptal ridges. Fine growth lines and moderately coarse wrinkles run transverse to the septal grooves. The calyx is moderately deep, and a thin laterally compressed axial column projects into its lower part. In several weathered specimens the column extends a few millimeters above the rest of the corallite. The neotype specimen is 30.0 mm in length and 12.7 mm in diameter, at the calyx. Eight other specimens in the same lot range from 12.1 mm to 33.3 mm in length and 8.2 mm to 10.4 mm in diameter.
The major septa are strong and straight, reaching nearly to the column. The arrangement in the upper part of the neotype is as follows: counter septum, 7 metasepta, alar septum, 3 metasepta, cardinal septum, 3 metasepta, alar septum, 7 metasepta, and counter septum again, a total of 24 major septa. The strong counter acceleration is also indicated by the septal arrangement in another specimen, which has the following septal plan: counter septum, 5 metasepta, alar septum, 3 metasepta, cardinal septum, 3 metasepta, alar septum, 5 metasepta, and back to the counter septum. In a mature example, the septa are nearly equal in size, except for the very short cardinal septum and the prolonged counter septum. Sections of the lower part of the corallite show the septa almost touching the column or even united to it and to each other by stereoplasm. The elements of the septa, except for the counter septum, are individually distinct and they can be differentiated from the column, however. The part of the corallite near the apex of the neotype is so filled with stereoplasm that it is difficult to identify the details of structure. Sections close to the apex, however, show that the median lamella of the counter septum extends at least to the axis, whereas the lamellae of the other septa nowhere invade this axial area. A section slightly more than halfway up the corallite reveals a distinct axial thickening of the septa. In the section just below the calyx the septa are slightly or not at all thickened axially.
The very thin and short cardinal septum lies in a conspicuous open fossula. The alar pseudofossulae are inconspicuous, even in youthful stages. Thin regular slightly anastomosing tabulae rise steeply from the periphery, flatten or slant downward slightly, and then rise to join the column. There are no dissepiments. The axial column is broadly oval in transverse section and is directly connected to the counter septum throughout most of the corallite, although free in the uppermost part. Transverse sections of the column near the calyx show the presence of fine lateral lamellae as well as the prominent median lamella.
Plate 1--All figures 3 times natural size. In each transverse section the counter septum is placed at the top. A larger PDF version is available.
Fig. 1-3, Lophophyllidium proliferum (McChesney), beds over coal no. 8, Trivoli cyclothem, Missouri series, Pennsylvanian, near Springfield, Illinois.--1a-c. Specimen (Illinois Geol. Survey and State Museum no. W4064b). a, Longitudinal section, b-c, Transverse sections.--2a-f. Specimen (Univ. Kansas no. 4761-21a). a, Longitudinal section containing counter septum, b, Longitudinal section containing cardinal septum, c-f, Transverse sections.--3a-e--Type specimen (Illinois Geol. Survey and State Museum no. W4064-a). a, Longitudinal section, b-e, Transverse sections.
Fig. 4, Lophophyllidium profundum (Edwards and Haime)?, recorded as questionably from the Lower Mercer limestone, lower Pottsville, Pennsylvanian, from northeastern Muskingum county, Ohio.--4a-d, Transverse thin sections of specimen (Ohio State Univ. no. 17850).
Fig. 5-7, Lophophyllidium confertum, n. sp., Lester limestone, Dornick Hills group, of Lampasas age, Pennsylvanian, southeast of Ardmore, Oklahoma.--5a-d, Type specimen (Univ. Kansas no. 6806-21c). a, Longitudinal section. b-d, Transverse sections.--6, Transverse section of specimen (Univ. Kansas no. 6806-21b).--7a, b, Transverse section of specimen (Univ. Kansas no. 6806-21a).
Weathered specimens show the exterior of the column to be covered with many somewhat anastomosing longitudinal ridges, slightly curved towards the counter septum and intersected by short transverse ridges. The counter side is marked by a sharp smooth longitudinal keel, but the other ridges show no relationship to the remaining septa.
In 1872 Meek (p. 144) described some specimens of a small column-bearing coral from Nebraska. These were compared with corals from the "Coal-Measures of Illinois" and reported to agree in all respects. Several longitudinal sections were reported, but only one fragment is illustrated and it shows distinct tabulae arching steeply toward the column. Inasmuch as tabulae were thought by Meek to be absent in the Cyathaxonidae, he referred Cyathaxonia prolifera to the genus Lophophyllum.
A number of years prior to the description published by McChesney, an internal mold of the calyx of a column-bearing coral from Flint Ridge, Ohio, had been described as Cyathaxonia profunda, n. sp., by Edwards and Haime (1851, p. 323). No illustrations accompanied this description or a later one in 1860 (Edwards and Haime, 1860, p. 331). Specimens of Flint Ridge corals, along with the rest of that fauna, were studied by Foerste in 1887 (p. 86) who identified them as Cyathaxonia prolifera McChesney. The next year Foerste (1888, p. 136) published a brief note giving his conclusion that the structure of the column in the Flint Ridge corals necessitates placing the species in Lophophyllum. L. proliferum was considered to be one of many variations of Lophophyllum profundum and Foerste thought that McChesney's species should be regarded as a junior synonym of L. profundum.
Since 1900 most American authors have considered Cyathaxonia prolifera as equivalent to C. profunda and almost no specimens have been assigned by them to Lophophyllum proliferum. Foreign authors, except Heritsch (1936a) uniformly have used the name proposed by McChesney for corals of this type. The Illinois specimens of Lophophyllidium proliferum that have been described differ from examples of L. profundum from Flint Ridge in the larger size and more cylindrical form of the corallite, more numerous septa and tabulae, and greater development of minor septa.
Lophophyllidium proliferum can be distinguished from L. dunbari Moore and Jeffords (1941, p. 83) by its larger size and the more curved character of the corallite, the greater size and symmetry of the axial column and the character of the arched tabulae. The curvature of the corallite in the Permian species is in the plane of the alar septa whereas the cardinal septum lies on the concave side of the corallite in L. proliferum. This species is separated from L. yakovlevi (Fomitchev, 1938) by the large and solid column, absence of a strongly marked breviseptal mature stage, and presence of distinct rhopaloid septa in immature parts.
Beds over Coal No. 8, Trivoli cyclothem, Missouri series, Pennsylvanian (Upper Carboniferous), near Springfield, Ill.
Illinois Geological Survey and Illinois State Museum no. W46064a. Other specimens studied include eight corallites that are associated with the neotype in the Illinois collection no. W40604 and two specimens from Springfield, Ill., contained in collections of the University of Kansas, no. 4761-21.
Lophophyllidium profundum (Edwards and Haime) ?
Plate 1, figure 4; plate 8, figure 4
Cyathaxonia profunda Edwards and Haime, 1851, Mon. Polyp. Fossiles Terr. Pal., Arch. Mus. Hist. Nat., vol. 5, p. 323; I860, Histoire naturelle des coralliaires ou polypes proprement dits: vol. 3, p. 331.
Cyathaxonia prolifera Foerste, 1887, Denison Univ., Sci. Lab., Bull., vol. 2, p. 86, pl. 8, fig. 15.
[not] Lophophyllum profundum Beede, 1900, Kansas Univ. Geol. Survey, vol. 6, pt. 2, p. 17, pl. 2, fig. 7, 7b—Woodruff, 1906, Nebraska Geol. Survey, vol. 2, pt. 2, p. 260, pl. 5, fig. 4.—Girty, 1915, U.S. Geol. Survey, Bull. 544, p. 19, pl. 2, figs. 1-6a, pl. 6, figs. 12,14.—Mather, 1915, Denison Univ., Sci. Lab., Bull., vol. 18, p. 91, pl. 1, figs. 11-13.—Plummer and Moore, 1921, Univ. Texas, Bull. 2132, p. 79, pl. 13, fig. 14, pl. 20, figs. 1, 2, 4, 5, pl. 23, figs. 3-6.—Morgan, 1924, Oklahoma Bur. Geol., Bull. 2, p. 192, pl. 32, figs. 2a-d.—Croneis, 1930, Arkansas Geol. Survey, Bull. 3, p. 134, pl. 27, fig. 1.—Kelly, 1930, Jour. Paleontology, vol. 4, p. 136, pl. 11, figs. 1, 2—Sayre, 1930, Kansas Geol. Survey, Bull. 17, p. 85, pl. 1, figs. 3-5.—Heritsch, 1936, Palaeontographica, Bd. 83, Abt. A, p. 108, pl. 17, figs. 15-18, text-fig.--pl. 2, fig. 9.
Small solitary corals straight or nearly straight and conical in form comprise this species. The moderately thick theca shows conspicuous rounded septal grooves and interseptal ridges with fine transverse growth lines. The calyx is not well shown by specimens available for my study, but it is probably deep. Two slightly crushed unsectioned specimens are 19.0 mm and 13.0 mm in length and 7.5 mm and 8.1 mm in diameter, respectively.
The septa in the upper portion are long and slightly to moderately rhopaloid. Their arrangement is as follows: counter septum, 5? metasepta, alar septum, 3 metasepta, cardinal septum, 3 metasepta, alar septum, 5 metasepta, and back to the counter septum again. Minor septa are not shown in any of the sections but seem to be indicated in the theca of the uppermost section. A lower section shows the major septa reaching nearly to the axial column and joined to it and to each other by steroplasm. The cardinal septum is short throughout. The thin long counter septum is greatly thickened axially to form the column.
An open cardinal fossula and large alar pseudofossulae are developed. A few thin uparched tabulae are present but are rare in upper portions. The axial column is directly connected to the counter septum except probably in the calyx. Transverse sections of early stages show a strongly marked median lamella running from the counter septum through the column. An upper transverse section shows this same median lamella and several other small lateral lamellae. These small radiating lamellae do not correspond to the other major septa. The uncentered longitudinal section shows only a few arched tabulae and indicates absence of dissepiments.
Description of L. proliferum by Edwards and Haime (1951, p. 323) was based on a mere external mold of the calyx of a column-bearing coral from Flint Ridge, Ohio. It was described as having a deep subcircular calyx that contains a straight column of subelliptical cross section and 24 well-developed thick major septa. No illustrations were given.
In 1887 Foerste (p. 86) described corals from Flint Ridge as Cyathaxonia prolifera. This species was characterized by him as including conical corals, nearly straight to curved below, bearing a thin theca that is marked by longitudinal grooves and ridges. The calyx is deep and nearly circular. Major septa are 20 to 28 in number, alternating minor septa being present only in the uppermost part of the calyx. The axial column is laterally compressed. A cardinal fossula and alar pseudofossulae are rather prominent. The largest of Foerste's specimens is reported to be 22 mm in length and 17 mm in diameter, at the calyx.
As indicated in the discussion of Lophophyllidium profundum, Foerste (1888, p. 136) later considered this Flint Ridge coral to be more properly identified as Lophophyllum profundum. Foerste (1888) also states that the characterization of L. profundum given by Edwards and Haime is very good, considering the nature of the specimens usually found.
The specimens here referred to L. profundum with question are from a collection loaned for study by J. W. Wells of Ohio State University. They were not collected at Flint Ridge, but are thought to come from the same horizon in Muskingum County, the next county east of that containing Flint Ridge. The lot sent by Dr. Wells includes two complete corallites, one longitudinal thin section, and four transverse thin sections, seemingly from the same corallite. This sectioned material does not show the extremely deep calyx figured by Foerste nor is the distinct inner wall indicated. Until more is known of the characters of L. profundum and more specimens are sectioned, these specimens may be assigned questionably to this species.
The specimens differ from L. proliferum in the smaller size and more conical form of the corallite, smaller number of septa and tabulae, and absence of minor septa.
The studied specimens are recorded with question as coming from the lower Mercer limestone, lower Pottsville, Pennsylvanian (Upper Carboniferous), northeastern Muskingum County, Ohio.
Ohio State Univ. no. 17850 (two corallites and five thin sections).
Lophophyllidium confertum, n. sp.
Plate 1, figures 5-7
The description of this species is based on a number of solitary long conical-cylindrical corallites that are straight or only very slightly curved in the plane of the alar septa. The moderately thick theca shows fine deep septal grooves and rounded longitudinal ridges. Fine growth lines and rare low wrinkles run transverse to the ridges and grooves. The calyx is deep and it contains a tall pointed spikelike column. The type specimen is 21.5 mm in height and 10.8 mm in diameter, just below the calyx.
A transverse section through the uppermost part of the type specimen reveals only broken and displaced septa. A section slightly lower shows 24 major septa, the alar not being determined from study of the sections. Another specimen shows the septal arrangement clearly in a section halfway up the corallite, as follows: counter septum, 6 metasepta, alar septum, 3 metasepta, cardinal septum, 3 metasepta, alar septum, 6 metasepta, and the counter septum again. In the upper parts the septa are long and only slightly thickened at the axial ends. The cardinal septum is short at all stages of development. The counter septum is extended to the axis to form the column in all except the very mature stages and then remains longer than other septa. Slightly lower sections show the long and rhopaloid major septa slightly joined to each other and to the column by stereoplasm. Still lower sections reveal that the septa are distinctly teardrop shaped and all are joined closely together and to the column by stereoplasm. Very short minor septa alternate with the major septa in upper portion.
The cardinal septum lies in a prominent open fossula. Alar pseudofossulae are visible in sections about halfway up in the corallite but are not apparent in the mature stages. Widely spaced thin tabulae rise from the periphery at an angle of about 45 degrees, flatten out slightly, and then rise abruptly as they join the axial column.
The thickening of septa and deposition of stereoplasm in the lower half of the corallite conceals most of the details of this part. This is a consistent feature of the specimens studied. The median lamellae of the septa can be recognized usually and they remain distinct where the septa are thickened by stereoplasm. In the solid portion of the corallite the column is not differentiated except for the extension of the lamella of the counter septum to and beyond the axis. In upper sections the column persists as a solid rodlike structure and passes from a broad oval shape to an elongated thin ellipse in successive transverse sections.
The coral named Lophophyllidium confertum is characterized by the narrow conical-cylindrical shape and by the thick deposit of stereoplasm in the lower half of the corallite. This species is readily distinguished from L. mundulum, n. sp., by its numerous tabulae, rhopaloid septa, and thick deposits of stereoplasm.
The calyx in most of the specimens of this species are broken and the septa of the uppermost sections are displaced. The thickening of the corallite in the apical region may have developed as a means of strengthening the long, thin-walled corallite against strong currents or waves.
Lester limestone, Dornick Hills group, of Lampasas age, Pennsylvanian (Upper Carboniferous), Murray Lake State Park, southeast of Ardmore, Oklahoma. Collected by R. C. Moore.
Univ. Kansas no. 6806-21c. Three other specimens from same locality were also studied.
Lophophyllidium mundulum, n. sp.
Plate 2, figure 1
Solitary steeply conical corallites, the lower part slightly curved in the plane of the alar septa, are included in this species. The thin theca shows deep narrow longitudinal grooves and broad rounded interseptal ridges. Transverse ornamentation consists of fine growthlines. The calyx is deep and a tall spikelike projection of the column occurs in the center. The type specimen is 20.0 mm in length and 11.7 mm in diameter, at the calyx.
Plate 2--All figures 3 times natural size. In each transverse section the counter septum is placed at the top. A higher-resolution PDF version is available.
Fig. 1, Lophophyllidium mundulum, n. sp., Pumpkin Creek limestone, 220 feet above Lester limestone, Dornick Hills group, of Lampasas age, Pennsylvanian, southwest of the Country Club, about 3 miles north of Ardmore, Oklahoma.--1a-d, Type specimen (Univ. Kansas no. 68-21a). a, Longitudinal section. b-d, Transverse sections.
Fig. 2, Lophophyllidium compressum, n. sp., Millsap Lake group, Des Moines series, Pennsylvanian, 3.5 miles east of Rochelle, Texas.--2a-c, Type specimen (Univ; Kansas no. 7208-21a). a, Longitudinal section. b,c, Transverse sections.
Fig. 3-4, Lophophyllidium murale, n. sp., about 8 feet above base of Memorial shale, Des Moines series, Pennsylvanian, from center south road in sec. 2, T. 33 S., R. 12 E., Montgomery County, Kansas.--3a-c, Specimen (Univ. Kansas no. 2615-21c). a, Longitudinal section. b,c, Transverse sections.--4a-c, Transverse sections of the type specimen (Univ; Kansas no. 2615-21b).
The two uppermost transverse sections show 26 major septa arranged as follows: counter septum, 7 metasepta, alar septum, 4 metasepta, cardinal septum, 4 metasepta, alar septum, 7 metasepta, and counter septum again. The cardinal septum is very short but the counter septum is attached to the column almost up to the calyx. The other major septa reach close to the column and are about equal in length. Very short minor septa appear about halfway up the corallite. In mature stages the major septa are thin and curve slightly towards the counter septum. No stage marked by development of conspicuous rhopaloid septa is observed in this species, but in the lower part of the corallite the septa are joined to each other and to the column by stereoplasm.
The cardinal fossula is large. No tabulae are shown in the transverse or longitudinal sections but there is a thick concealing deposit of stereoplasm in the lower part of the corallite.
This species has relatively simple internal structures. No tabulae are recognized but it seems probable that they actually are present, though concealed by stereoplasm. Malonophyllum has been assumed to contain corals similar to Lophophyllidium but without tabulae. This feature alone may not be usable for precise generic separation. L. newelli, L. minutum, L. distinctum, L. sp. A, and L. sp. B also have very few tabulae or seem entirely to lack them. These corals and the Permian species M. kansasense are characterized by very rapid development of the corallite and restriction of internal structures to the lower part. L. mundulum, on the other hand, closely resembles most species of Lophophyllidium in the septal arrangement, rate of development, and long relatively slender form.
Lophophyllidium mundulum is distinguished from L. confertum, n. sp., by the lack of rhopaloid thickening of the septa, little stereoplasm except at the column, and absence of recognizable tabulae.
Pumpkin Creek limestone, 220 feet above Lester limestone, Dornick Hills group, of Lampasas age, Pennsylvanian (Upper Carboniferous). Collected by R. C. Moore, southwest of the Country Club, about 3 miles north of Ardmore, Oklahoma.
Univ. Kansas no. 68-21a.
Lophophyllidium compressum, n. sp.
Plate 2, figure 2; plate 8, figure 1
This species comprises medium-sized solitary conical corallites that are distinctly curved in the plane of the alar septa or nearly so. The moderately thick theca bears well-defined septal grooves that are about as broad as the rounded ridges. Prominent wrinkles and fine growth lines run transverse to the septal markings. The calyx is deep and a broad laterally flattened column projects nearly to its rim. The type specimen which is slightly above average size, is 25.6 mm in length and 15.2 mm in diameter.
The uppermost transverse section of the type specimen shows 32 unequal major septa, arranged as follows: counter septum, 9 metasepta, alar septum, 5 metasepta, cardinal septum, 5 metasepta, alar septum, 9 metasepta, and the counter septum again. The cardinal septum is very short, but the counter septum extends beyond the middle of the coral, its inner or axial edge being thickened to form the laterally compressed column. In the type specimen, a transverse section slightly below the calyx shows the septa to be of unequal and varying lengths. The majority reach close to the column and are much thickened axially. The others are about two-thirds as long and only slightly rhopaloid. In immature stages the septa are slightly rhopaloid, closely packed axially, and thickened by considerable stereoplasm. At successively higher positions in the corallite, the amount of this deposit is diminished and the septa are accordingly more distinct. The minor septa are introduced first in the counter quadrants in an irregular manner and remain very short. The cardinal fossula is conspicuous but alar pseudofossulae are rather poorly defined at all stages. The thin regularly spaced tabulae rise gradually from the periphery and then curve gently downward. Just before joining the column they once more turn slightly upward. These tabulae are seen in longitudinal section as nearly symmetrical curves, with the concave side downward. The laterally compressed column is distinct and solid at all stages, although the axial portion of the early part of the corallite is strengthened by deposition of stereoplasm. No vertical striae are visible on the column.
This species is characterized by the broadly conical form of the corallite, the thick solid axial column, and the nearly flat tabulae that dip downward near the column. It can be distinguished easily from Lophophyllidium murale, n. sp., by its shorter cardinal septum, more rhopaloid septa, and the absence of parallel open spaces on either side of the counter-cardinal plane.
Millsap Lake group, Des Moines series, Pennsylvanian (Upper Carboniferous). Collected by R. C. Moore in a small stream bed 0.8 miles from highway, 3.5 miles east of Rochelle, Texas.
Univ. Kansas no. 7208-21a. Other studied material includes about a dozen corallites and sectioned specimens.
Kansas Geological Survey, Geology
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